Air cycle cooling system with rotary condensing dehumidifier

ABSTRACT

An air cycle cooling system having a rotary condensing dehumidifier wherein the air from the compressor is passed through the vanes of a transverse flow heat exchanger with the cooled air from the expansion turbine being passed over the external surfaces of the vanes to thereby cool the air within the vanes. The cooling of the air within the vanes causes the moisture to be condensed. The water in the vanes is moved along with the moving air by viscous interaction. The water collects in the end member of the transverse flow heat exchanger and is removed by centrifugal force through poppet valves.

United States Patent [1 1 1 3, ,1 Zara et a]. 1 Apr. 1, 1975 [54] AIR CYCLE COOLING SYSTEM WITH 2,979,916 4/1961 Mason 62/172 ROTARY CONDENSING DEHUMIDIFIER 3,222,883 12/1965 Glaspie 62/93 Inventors: Eugene A. Zara, Dayton; Lawrence L. Midolo, Centerville; William C. Savage, Xenia, all of Ohio The United States of America as represented by the Secretary of the Air Force, Washington, DC.

Filed: May 9, 1974 Appl. No.: 468,326

Assignee:

US. Cl 62/272, 62/93, 62/150,

62/402 Int. Cl. F25d 21/00 Field of Search 62/93, 150, 272, 172

References Cited UNITED STATES PATENTS 2/1952 Carson ..62/150 7/1960 Brown ..62/272 3,623,332 11/1971 Fernandes 62/172 Primary Examiner-William J. Wye

Attorney, Agent, or Firm-Harry A. Herbert, Jr.; Richard .1. Killoren [57 ABSTRACT An air cycle cooling system having a rotary condensing dehumidifier wherein the air from the compressor is passed through the vanes of a transverse flow heat exchanger with the cooled air from the expansion turbine being passed over the external surfaces of the vanes to thereby cool the air within the vanes. The cooling of the air within the vanes causes the moisture to be condensed. The water in the vanes is moved along with the moving air by viscus interaction. The water collects in the end member of the transverse flow heat exchanger and is removed by centrifugal force through poppet valves.

3 Claims, 3 Drawing Figures raga/Mr AIR CYCLE COOLING SYSTEM WITH ROTARY CONDENSING DEHUMIDIFIER Y The invention described herein may be manufactured and used by or for the Government of the United States for all governmental purposes without the payment of any royalty.

BACKGROUND OF' THE INVENTION In air cycle cooling systems for aircraft, it is desirable to increase the cooling capacity of such systems to thereby reduce their weight and size for a given aircraft. The patent to Carson et al, U.S. Pat. No. 2,586,002, shows one type of air cycle cooling system for aircraft. In this system, the cooled expanded air from the expansion engine is passed across a swirl chamber which cools and removes water from the input air to the expansion engine. A more efficient cooling system for the input air to the expansion engine would provide drier air which could be expanded to a lower temperature thus increasing the cooling capacity of the system.

BRIEF SUMMARY OF THE INVENTION According to this invention, a conventional two phase heat exchanger, wherein a liquid normally is passed through the hollow blades of an impeller with a cooling gas being passed over the blades of the impeller to thereby cool the liquid, is used with air passing through the hollow blades to thereby provide more efficient cooling of the air withinthe blades. The condensed water in the blades is moved axially within the blade passages by the air passing through the blades. The water is centrifuged to the outer wall of the exit manifold of the heat exchanger and is passed out of the manifold through poppet values to an external water recovery system. The dry air passes to the air cycle expansion turbine and over the outer portion of the heat exchanger and then to the aircraft cabin.

IN THE DRAWING FIG. I is a partially cut away view of an air cycle cooling system with a condensing dehumidifier according to the invention.

FIG. 2 is a sectional view of the device of FIG. I along the line 22.

FIG. 3 shows a modified water extraction apparatus for use with the device of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION Reference is now made to FIG. 1 of the drawing wherein a conventional transverse flow heat exchanger 10, such as described in the patents to Laing, U.S. Pat. Nos. 3,347,059 and 3,424,234, is modified for use as a condensing dehumidifier in an air cycle cooling system such as described in the patent to Carson et al, U.S.

Pat. No. 2,586,002. Air from the compressor, not

shown, is supplied to the inlet 12 to the rotary heat exchanger element 14 which is driven by a belt 16 and motor 18. Rotary seals, not shown, are provided between end conduits, 22 and 24, of the rotary element 14 and the inlet and outlet conduits 25 and 26 respectively. The air passes through end channel 27 and then through vane members 29 to a second end member 31. The air then passes through an expansion turbine, shown in block 33, in a manner similar to that described in the US. Pat. No. 2,586,002. The turbine may be used to provide shaft power for auxiliary compression or maybe used for other purposes such as driving electrical generators} The cooled air from the expansion turbine is supplied to a conditioned compartment, not shown, through a conduit 35, by means of the transverse flow heat exchanger fan 14. As the air passes over the vanes 29, it

cools theair within the vanes to condense moisture in the air. The moisture is removed from rotary heat exchanger'by providing a plurality of poppet valves 38 around the periphery of the heat exchanger end member 31. When no water is present, in the end member, the valves 38 will remain closed. The springs of the poppet'valves are set to maintain the valves closed against the *air'pressure within the system which would be of the order of I00 psia. When water collects in the end member, the centrifugal force on the water together with the air pressure overcomes the spring of the poppet valves to allow the water to escape through the poppet valves into nozzle members 40. This water then passes through nozzle members 40 into an annular trough 42 and outlet 44.

In the operation of the device, air from a compressor, not shown, is supplied at inlet 12. The air passes through the vanes 29 to end member 31 and then out through conduits 24 and 26 to the expansion turbine 33. The air is cooled by expansion in the expansion tur-' bine and then passed through conduit 35 to the rotary heat exchanger and then to the compartment to be cooled. The air in conduit 35 cools the air in vanes 29 as it passes over them. The water condensed in the vanes 29 is moved by viscus interaction with the air in the vanes to end member 31 where it collects and is passed out through poppets 38 to be collected in trough 42 from which it passes to outlet 44.

It places where leakage from trough 42 is not a problem, the device of FIGS. 1 and 2 may be used. When leakage is a problem, some means is needed to provide a seal for trough 42. An alternative arrangement is shown in FIG. 3.

In this device, the nozzle 40 and trough 42 are replaced by reservoirs 50, which are sealed to end member 31. Tubular members 52 carry the water to an annular reservoir 54 which is secured to conduit 24'. Openings 55 are provided in the reservoir 54 so that water may pass to an annular trough 56 which is sealed to reservoir 54 by O-ring seals or other seal means. The water in trough 56 can pass out through conduit 58.

The water is able to flow inward through conduit 52 against the centrifugal force since it will be driven by the air pressure in end member 31. By bringing the water inward to reservoir 54, a smaller exit trough and seals can be used.

There is thus provided a condensing dehumidifier for an air cycle cooling system which provides more efficient cooling to provide drier air which permits use of a system with increased cooling capacity.

We claim:

1. In an air cycle cooling system having an expansion turbine; at dehumidifier having a first air flow path and a second air flow path; means for supplying high pressure air to said first flow path; means for supplying air from the first flow path to said expansion turbine; whereby said air is cooled to a low temperature; means for supplying cooled air from said expansion turbine to the second flow path of said dehumidifier whereby the moisture in the air in said first flow path is condensed to form water; said dehumidifier comprising a transverse flow fan having a rotary fan member and an air duct surrounding the fan member; said fan member having a plurality of hollow vanes forming the first flow path within the vanes; said air duct forming the second air flow path through the rotary fan member external to the vanes; said rotary fan member having an end member for collecting water formed by the moisture condensed in the first flow path within said vanes; means, responsive the centrifugal force on the water in said end member for removing the water from said end member.

2. The device as recited in claim 1 wherein said means for removing the water from the end member includes a plurality of poppet valves, adapted to remain connected to said annular trough. 

1. In an air cycle cooling system having an expansion turbine; a dehumidifier having a first air flow path and a second air flow path; means for supplying high pressure air to said first flow path; means for supplying air from the first flow path to said expansion turbine; whereby said air is cooled to a low temperature; means for supplying cooled air from said expansion turbine to the second flow path of said dehumidifier whereby the moisture in the air in said first flow path is condensed to form water; said dehumidifier comprising a transverse flow fan having a rotary fan member and an air duct surrounding the fan member; said fan member having a plurality of hollow vanes forming the first flow path within the vaneS; said air duct forming the second air flow path through the rotary fan member external to the vanes; said rotary fan member having an end member for collecting water formed by the moisture condensed in the first flow path within said vanes; means, responsive the centrifugal force on the water in said end member for removing the water from said end member.
 2. The device as recited in claim 1 wherein said means for removing the water from the end member includes a plurality of poppet valves, adapted to remain close in response to said high pressure air alone and adapted to open in response to said high pressure air and the centrifugal force on the water when water collects in the end member; means, positioned adjacent the poppet valves, for carrying the water, passing through the poppet valves, away from the end member.
 3. The device as recited in claim 2 wherein said means for carrying the water away, includes a nozzle, surrounding each poppet valve, secured to said end member; an annular stationary trough positioned in water receiving relation to the nozzles; a drain outlet connected to said annular trough. 